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2 votes
a diagram shows the part of graph y=ax^2 which is a parabola , it also gives me the coordinates (-3,45) .How do i find the value of a ??

2 Answers

4 votes
y = ax²
45 = a(-3)²
45 = a(9)
45 = 9a
9 9
5 = a
User Gilfoyle
by
6.7k points
5 votes
you plug in the x and y coordinates 45=a3^2
45=9a
divide 9 on both sides
a=5
User Lsaffie
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7.2k points